let pp:string|number|boolean = 42
pp = "wfew"

let arr:(string|boolean|number)[] = [342,"wer",true]

let a:432|string = '111'


type aa = string|number|boolean
type aaa = string
interface Per{
    age:number,
    name:string,
    height?:number
}
type aaaa = Per

let vv:aa = 'aa'
let vvv:aaa = 'aaa'
let vvvv:aaaa = {
    name:'xiaoming',
    age:43
}
 
interface SubPer extends Per{
    id:number
}
let lll:SubPer = {
    name:'zs',
    age:34,
    id:1,
    height:188
}

type pppp1 = aaaa &{id:number}
let llll:pppp1 ={
    name:'zs',
    age:34,
    id:1
}
let e1:unknown = 56;
console.log((e1 as number).toFixed(2))

let kkk:string|number = "xiaoming"
console.log(kkk.length)
function get1():string|number{
    return 'zs'
}
let res6 =get1()
if(typeof res6 === "string"){
    res6.length
}